defaultroute polls for up to defaultroute_delay seconds, 30 by
default, whenever an interface uses DHCP or SLAAC, and stops as soon as
a default route appears in either family. Nothing ordered it against
routing, which installs the static defaultrouter, so which of the two
runs first falls out of rc(8)'s skip filters and the set of installed
third-party scripts. Where defaultroute wins, a static route cannot
end the poll, and a host whose SLAAC router never advertises one waits
the full timeout on every boot.
Require routing. Blocking until DHCP finishes was never what this poll
guaranteed. synchronous_dhclient=YES is what actually does that.
PR: 287887
Submitted by: Igor Gusarov <Igor.Gusarov@kaspersky.com>